1. Field of the Invention
The present invention relates to a broadcast receiving apparatus that receives digital broadcasting and displays an image according to a broadcast program and an image according to an application, in synchronization with each other.
2. Description of the Related Art
In digital terrestrial broadcasting, a broadcast program can be distributed together with an application in liaison with the broadcast program. The image according to the broadcast program is displayed in synchronization with execution of the application in a manner described below. A transport stream (TS) that can be obtained by demodulating a broadcast signal, includes a normal play time (NPT) as the data indicating a passage of time from a start of a program. The application is programmed such that each processing is executed in synchronization with the program in periodic reference to the NPT.
Japanese Patent Application Laid-open No. 11-27641 discusses, according to event activation information supplied from a broadcast station via a broadcast stream, a television (TV) receiver that causes an application object to be activated. As a result, a synchronized control can be performed between a broadcast stream and an application per not an application unit but per an object unit.
Further, Japanese Patent Application Laid-open No. 2009-130821 discusses a technique for realizing an audio playback in synchronization with an image display by delaying a sound according to a delay time of the image display.
In the conventional synchronization control method, since a time period required for image processing performed by the broadcast receiving apparatus differs depending on a image quality mode for displaying the image, sufficiently accurate synchronization could not always be achieved between the image according to the broadcast program and the image according to the application.